Enhancing biosensor capabilities through laccase immobilization in nanostructured Langmuir-Blodgett films for phenol detection

Author(s)

Machado, A. C. ; Salvo-Comino, C. ; Rodriguez-Mendez, M. L. ; Caseli, L.

• Document type: Journal article
• Source: RESULTS IN SURFACES AND INTERFACES; v. 18, p. 9-pg., 2024-11-27.

Abstract

Fabricating nanoscale structures combining various elements with specific functionalities is a pertinent strategy for enhancing sensor capabilities. In this study, we immobilized Laccase (Lac) in a biomimetic environment provided by a nanostructured Langmuir-Blodgett (LB) film of an amphiphilic material (octadecylamine, ODA), where poly(3-hexylthiophene-2,5-diyl) (P3HT) has been coimmobilized as the electron mediator. Tensiometry demonstrates that the enzyme is incorporated in the floating monolayers efficiently. The monolayers were transferred to solid substrates as LB films and characterized using UV-vis and infrared spectroscopies and Atomic Force Microscopy, exhibiting a quasi-ordered structure with low roughness. The films' ability to detect phenols was evaluated through enzymatic activity estimation using colorimetric and voltammetry measurements against vanillin, catechol, and pyrogallol. Our results demonstrate that the electrochemical response depends on the phenol's nature, with limits of detection for vanillin, catechol, and pyrogallol at 1.10.10(-6), 2.13.10(-7), and 2.07.10(-7) mol.L-1, respectively. Additionally, the intensity of the response does not correlate with film thickness, confirming that the electrochemical reaction is a surface phenomenon for catechol and pyrogallol. We believe this study provides valuable insights into phenol detection in the food industry, which is crucial for ensuring food safety, quality, and authenticity by aiding in regulatory compliance, process optimization, and product preservation. (AU)

• FAPESP's process: 22/03736-7 - Nanostructured interfaces for the investigation of bioactive substances in cell membrane models and for the construction of optoelectronic devices
• Grantee: Luciano Caseli
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 22/04241-1 - Langmuir-Blodgett films of the enzyme laccase for the detection of phenolic derivatives
• Grantee: André Campos Machado
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 23/00329-4 - Development of biosensors for phenol compounds utilizing Langmuir and Langmuir-Blodgett films containing laccase
• Grantee: André Campos Machado
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate